#! /usr/bin/python

# Smallest multiple
#
# 2520 is the smallest number that can be divided by each of 
#  the numbers from 1 to 10 without any remainder.
# What is the smallest positive number that is evenly divisible
#  by all of the numbers from 1 to 20?

# greatest common divisor
def gcd(a, b):
    return a if b==0 else gcd(b, a%b)

# lowest common multiple
def lcm(a, b):
    return a * b / gcd(a, b)

print reduce(lcm, range(1,21))

